COMPOSITE REFRACTORIES FOR THE MOST LOADED AREAS
OF BLAST FURNACES
A. E. Paren’kov,
F. L. Skuridin,
and A. N. Pyrikov
Translated from Novye Ogneupory,No.2,pp.3–6,February 2009.
Original article submitted October 14, 2008.
The service of a blast furnace is mainly governed by the state of the lining of the hearth and the bottom. Con
temporary specifications are considered for it based on the example of the largest blast furnaces in the world:
No. 5 with a net volume of 5580 m
(OAO Severstal’, Cherepovets, Russia) and No. 2 with an internal volume
of 5775 m
(Nippon Steel Corporation, Oita, Japan). It is proposed in comparing refractory quality, apart from
traditional properties, to consider a mineralogical (phase) criterion for oxide heat resistance, i.e. heat energy
Keywords: blast furnace, lining, refractories, properties, composition.
It follows from evaluation of the state of blast furnace
production in Russia and the world that a blast furnace, as the
main metallurgical unit, will also function in the XXI cen-
tury. In order to provide high productivity and a normal
course for a blast furnace it is important to monitor the state
of its lining. The lining is made of different refractory mate-
rials using different oxides: Al
, MgO, Cr
[1 – 5]. Depending on the nature of the physicochemical me-
dium in some or other part of a furnace different refractories
are used. The shaft, hearth and upper part of the well of a fur
nace are lined with high-alumina blocks. In recent years
there has been extensive use of torcreting. It is carried out in
order to apply concrete mixes as protection of the blast fur
nace coolers from temperature and mechanical action.
Within a blast furnace the charge materials and gases
move in counterflow causing wearing and erosive action on
the lining. Different zones of the blast furnace have the fol
– the upper half of the shaft has continuous charge
movement, action of sooty carbon and zinc;
– the lower half of the shaft has reaction of the lining
with primary iron slags, the action of zinc, and alkali metal
– the bosh has movement of materials and gases, action
of zinc and alkali metal compounds;
– the shoulders have increased temperature of the me-
dium, continuous movement of iron and coke, chemical ac-
tivity of slags, pressure of the charge and gases;
– the hearth has the maximum temperature of the me-
dium, continuous movement of liquid products, chemical ac-
tivity of melt and gas products;
– the bottom has a high temperature and pressure of liq-
uid products and gases.
The main effect on the life of refractories of the hearth
and the bottom are the high temperature of the medium, pres
sure of liquid products of the melt and their chemical activ
ity, and in the upper region of the shaft it is the mechanical
action of gases and materials, chemical activity of the pri
mary and intermediate slags, zing and alkali metal com
For the hearth zone the most important properties of the
lining are thermal conductivity, porosity and wear resistance.
Therefore in the lower part of the bottom materials
refractories are used with high thermal conductivity: carbon,
graphite, silicon carbide. Graphite refractories prevent pene
tration of liquid iron into the lining in its upper layer. Liquid
iron is in contact with the ceramic lining, that protects carbon
blocks from abrasive action of moving liquid metal and
slags. Wear of the hearth walls mainly occurs as a result of
the extreme thickness of the walls, as a result of insufficient
size of gaps, compensating thermal expansion, and unsatis
factory material quality. Thermal spalling and cracking of the
hot surface of the walls starts under the action of high tem
perature and therefore compensation of thermal deformation
of the horizontal cross section is provided. In order to pre
Refractories and Industrial Ceramics Vol. 50, No. 1, 2009
1083-4877/09/5001-0013 © 2009 Springer Science+Business Media, Inc.
State University of Technology “Moscow Institute of Steels and
Alloys”, Moscow, Russia.
OOO Ogneupor Trade group, Moscow, Russia.